Hypothermia
When people play in the wilderness, one danger they commonly recognize
is hypothermia, the lowering of the body’s core temperature from its nor
mal level of 98.6 ̊F (37 ̊C) to 95 ̊F (35 ̊C) or lower.
The onset of hypothermia is slow and usually undetected by the vic
tim. Even in ice water it may take 30 minutes or more to become hypo
thermic. In cold air, it takes hours or even days.
If you are stranded in a cold air environment, the cold/wet/wind triad
can be deadly. Many folks set off on a pleasant day with minimal extra
clothing and supplies, only to be overtaken by wind and rain. These con
ditions can be deadly if you don’t have a day pack with some extra cloth
ing. Traveling partners need to watch each other for signs of hypothermia,
which can be described as the “umbles”: grumbles, fumbles, stumbles, and
tumbles. Change in personality, loss of fine and gross motor movement,
and shivering are potential signs that you are too cold. Get into a shelter,
rest, and ingest highcalorie drinks and foods until you feel better.
Frostbite
Frostbite is the freezing of tissue. Mild frostbite involves freezing superfi
cial layers—skin—while severe frostbite involves freezing flesh below the
skin. Obviously, the deeper the freezing, the more damage is done.
Water within tissues freezes and forms ice crystals, and these
sharp fragments damage the tissue (one reason why you should never
rub the site of frostbite). The major problem resulting from frostbite is
the destruction of capillaries. These small vessels are responsible for the
exchange of oxygen and nutrients between the blood and tissue. Once
tissue is thawed, the frostbitten area can become flushed as blood flow
returns to it. But because the capillaries have been destroyed, the blood
cannot provide lifegiving oxygen.
Our advice to outdoors enthusiasts is this: Never accept numbness.
As nerves get progressively colder, sensations progress from cold, to pain,
to numbness, to nothing. Numbness is a warning that tissue is nearing the
freezing point. At that point, you must get the numb body part out of the
cold or add insulation. Simply putting your hands in your armpits can all
but guarantee that they won’t freeze. If your fingers freeze even when they
are in your armpits, your biggest problem isn’t frostbite.
(^268) | Survive!